Roller wrench

ABSTRACT

The invention relates to a roller wrench comprising: a body with a circular chamber; a driving member being a regular polygonal component capable of rotating in the chamber; a plurality of rollers installed in the chamber, each of the rollers is located between a side of the driving member and a peripheral wall of the chamber; a reversing knob capable of driving the rollers to move in the chamber so that each of the rollers moves between two edges of each of sides of the driving member; and at least one elastic positioning component installed on one of the sides of the driving member, and capable of elastically moving into the driving member or protruding from a peripheral surface of the driving member; the elastic positioning component is moved into the driving member when being compressed; and is protruded from the driving member when not being acted on by an external force; and each of the elastic positioning components limits one of the rollers, thereby positioning the rollers and the reversing knob.

CROSS REFERENCE TO RELATED APPLICATION

This patent application claims priority to U.S. Provisional PatentApplication Ser. No. 62/981,322, entitled “ROLLER WRENCH”, filed on Feb.25, 2020, and priority to U.S. Provisional Patent Application Ser. No.63/003,775, entitled “ROLLER WRENCH”, filed on Apr. 1, 2020.

BACKGROUND OF THE INVENTION Field of Invention

The invention is related to wrenches, and more particularly to a rollerwrench.

Related Art

FIG. 1 shows a conventional reversible roller wrench 10, a drivingmember 14 is installed in a circular chamber 12 of a head 11, thedriving member 14 has six sides 15, a center of each of the sides 15 hasa concave portion 152, and the concave portion 152 makes two edges ofeach of the sides 15 respectively form a latching surface 151. Sixrollers 16 are installed between the six sides 15 and a peripheral wall13 of the chamber 12 respectively. A reversing knob 17 is installed on atop of the head 11, and six walls 171 are protrudingly provided on abottom surface of the reversing knob 17 and six limiting grooves 172 areformed between the six walls 171; the six rollers 16 are respectivelylimited in the six limiting grooves 172, as shown in FIG. 2. Thereversing knob 17 can be rotated and positioned at two positions by thethree elastic positioning components 18. Please refer to FIGS. 1 and 3,the three elastic positioning components 18 are respectively installedin three holes 173 provided on the bottom surface of the reversing knob17, a top surface of the driving member 14 is provided with two sets ofpositioning holes 153 and 154, and the elastic positioning components 18can be elastically snapped into either set of the two sets ofpositioning holes 153 and 154.

When the reversing knob 17 is rotated in one direction, the reversingknob 17 can be switched to be positioned at a first position, as shownin FIG. 2. At this time, one ends the three elastic positioningcomponents 18 are elastically snapped into the first set of thepositioning holes 153, and this makes each of the rollers 16 to contactwith the latching surface 151 (such as the latching surface on the leftedge) at one edge of each of the sides 15; when the reversing knob 17 isrotated in another direction, the reversing knob 17 can be switched to asecond position, and the rollers 16 are respectively moved to anotheredge of each of the sides 15 so that each of the rollers 16 is incontact with the latching surface 151 (for example, the latching surfaceon the right edge) at another edge of each of the sides 15; and theelastic positioning components 18 are elastically snapped into thesecond set of the positioning holes 154 respectively. By switching thereversing knob 17 to the first position or the second position, theroller wrench 10 has a reversing function.

Each of the rollers 16 has a disengaging-engaging function with thelatching surface 151 with which the roller 16 is in contact. Taking thelatching surface 151 on the left edge of FIG. 2 as an example, there isan included angle 0 between each of the latching surfaces 151 and theperipheral wall 13 of the chamber 12, on the left side of the latchingsurface 151, a gap between the latching surface 151 and the peripheralwall 13 gradually decreases, and on the right side of the latchingsurface 151, a gap between the latching surface 151 and the peripheralwall 13 gradually increases. When the wrench 10 is turned clockwise, theroller 16 moves toward a direction of a small gap, and therefore, eachof the rollers 16, each of the corresponding latching surfaces 151 andthe peripheral wall 13 of the chamber 12 are latched with one another,and the wrench 10 can drive the driving member 14 to turn clockwise;conversely, when the wrench 10 is turned counterclockwise, the roller 16moves toward a direction of a large gap, each of the rollers 16, each ofthe corresponding latching surfaces 151 and the peripheral wall 13 ofthe chamber 12 cannot be latched with one another, and the wrench 10cannot drive the driving member 14 to rotate.

The conventional roller wrench 10 has a certain number of disadvantagesthat needs to be overcome. If the reversing knob 17 needs to bepositioned at the first position or the second position, the top surfaceof the driving member 14 and the bottom surface of the reversing knob 17have to be respectively disposed with the two sets of the positioningholes 153, 154 and the holes 173 for installing the elastic positioningcomponents 18 and generating elastic positioning function, however, thepositioning holes 153, 154 and the holes 173 increase the manufacturingcosts and the complexity of the manufacturing process. Furthermore, dueto the limitation of the disposing locations, the positioning holes 153,154 have small hole diameter and shallow depth, which makes it easy forthe elastic positioning components 18 to slide out of the positioningholes 153, 154, such uncertain and unreliable positioning will result inthe rollers 16 being unable to be effectively positioned in theirpositions.

SUMMARY OF THE INVENTION

The invention aims to solve the above-disclosed drawbacks, and its mainobject is to provide a roller wrench and to make the roller wrenchcapable of providing reliable positioning function, and effectivelypositioning rollers and a reversing knob of the roller wrench in theirpositions.

Another object of the invention is to provide a roller wrench, and tomake the roller wrench easy to be manufactured and the manufacturingcosts can be reduced.

In order to achieve the above-mentioned objects, the roller wrenchprovided by the invention comprises:

a body with a head, a circular chamber disposed in the head;

a driving member being a regular polygonal component with a plurality ofsides, the driving member being installed in the chamber of the head andcapable of rotating in the chamber;

a plurality of rollers installed in the chamber and respectively locatedbetween the sides of the driving member and a peripheral wall of thechamber; and

a reversing knob rotatably installed on the head and capable of drivingthe rollers to move in the chamber, so that each of the rollers movesbetween one edge and another edge of each of the sides of the drivingmember; further comprising:

at least one elastic positioning component, each of the elasticpositioning components is installed on one of the sides of the drivingmember, and capable of elastically moving into the driving member orprotruding from a peripheral surface of the driving member; the elasticpositioning component is moved into the driving member when beingcompressed; and is protruded from the driving member when not beingacted on by an external force;

at least one of the rollers is limited by the at least one elasticpositioning component to position the rollers and the reversing knob;when the reversing knob is rotated, the roller presses the elasticpositioning component to make the roller move from one of the edges tothe other edge of the side of the driving member.

Thereby, the elastic positioning component is capable of positioning therollers and the reversing knob, and an elastic positioning structure ofthe roller wrench is relatively simple, easy to be manufactured and canreduce the manufacturing costs.

Preferably, each of the elastic positioning components is located at acenter of the corresponding side that the elastic positioning componentis installed on.

Preferably, at least one installation hole is recessed on at least oneof the sides of the driving member; the at least one elastic positioningcomponent is installed in the installation hole and can be moved into orprotruded from the installation hole.

Preferably, the elastic positioning component has an elastic element andan abutting member, which are installed in the installation hole, theabutting member is abutted by the elastic element and protruded from theperipheral surface of the driving member; and the abutting member of theelastic positioning component limits one of the rollers.

Preferably, one end of each of the rollers is rotatably pivotallyconnected to one end surface of the reversing knob; when the reversingknob is rotated, the reversing knob drives the rollers to displace.

BRIEF DESCRIPTION OF THE DRAWINGS

The objects, features, and achieved efficacies of the invention can beunderstood from the description and drawings of the following preferredembodiments, in which:

FIG. 1 is an exploded perspective view of a conventional roller wrench;

FIG. 2 is a combinational cross-sectional view of FIG. 1;

FIG. 3 is a cross-sectional view taken along section line 3-3 of FIG. 2;

FIG. 4 is a perspective view of a roller wrench of a first preferredembodiment of the invention;

FIG. 5 is an exploded perspective view of FIG. 4;

FIG. 6 is a cross-sectional view taken along section line 6-6 of FIG. 4;

FIG. 7 is a top view of a driving member of the first preferredembodiment of the invention;

FIG. 8 is a cross-sectional view taken along section line 8-8 of FIG. 6;

FIG. 9 is a cross-sectional view taken along section line 9-9 of FIG. 6showing that rollers of the roller wrench are positioned at firstpositions;

FIG. 10 is similar to FIG. 9 showing that the rollers of the rollerwrench are positioned at second positions;

FIG. 11 is an enlarged schematic view of the rollers, latching surfacesand a peripheral wall of a chamber of the wrench;

FIG. 12 is similar to FIG. 8 and is a cross-sectional view of the rollerwrench of a second preferred embodiment of the invention;

FIG. 13 is an exploded perspective view of the roller wrench of a thirdpreferred embodiment of the invention;

FIG. 14 is a combinational cross-sectional view of FIG. 13 and ahorizontal cross-sectional view showing that the rollers are positionedat the first positions; and

FIG. 15 is similar to FIG. 14 showing the rollers are positioned at thesecond positions.

DETAILED DESCRIPTION OF THE INVENTION

Please refer to FIGS. 4 to 6 for a roller wrench 20 of a first preferredembodiment of the invention, the roller wrench 20 comprises: a body 30,a driving member 40, a plurality of rollers 50, a reversing knob 60 andat least one elastic positioning component 70.

The body 30 has a head 31 and a shaft 36 connected to each other, andthe head 31 is located at a front end of the shaft 36. A top surface ofthe head 31 is inwardly recessed with a circular chamber 32; and abottom surface of the head 31 is penetrated, such as by disposing with athrough hole 34.

Please refer to FIG. 7 in conjunction with the above figures. Thedriving member 40 is a regular polygonal component, such as a regularquadrilateral, a regular pentagon, a regular hexagon, a regular octagon,etc., and has a plurality of sides. In the preferred embodimentdisclosed in this specification, the driving member 40 is a regularhexagonal component as an example, and has six sides 41. Each of thesides 41 of the driving member 40 has a central area 42 which is a flatsurface; each of the sides 41 is respectively provided with a concave(recessed toward an inside of the driving member 40) latching surface 44on two sides of the central area 42, each of the latching surfaces 44has an inner side 441 connected to the central area 42 and an outer side442 away from the central area 42. A concave state of each of thelatching surfaces 44 is gradually recessed inwardly from the inner side441 to the outer side 442, so that the outer side 442 is recessed fromeach of the sides 41. Although the latching surfaces 44 are flat inappearance, each of the latching surfaces 44 can be a gradually concavedarc surface. On each of the sides 41, an included angle α is formedbetween each of the latching surfaces 44 and the central area 42, theincluded angle α is between 1 degree and 10.4 degrees, or between 2.2degrees and 10.4 degrees, preferably between 4.3 degrees and 8.8degrees. A protrusion 411 is further provided between the two adjacentsides 41, and each of the protrusions 411 is formed between the outersides 442 of the two adjacent latching surfaces 44, which is capable ofincreasing a structural strength of the driving member 40. The drivingmember 40 is installed in the chamber 32 of the head 31 and capable ofrotating in the chamber 32. In addition, the driving member 40 is usedfor coupling and driving threadedly-connecting elements such as nuts orbolts, or coupling sockets. A center of the driving member 40 can beprovided with a polygonal sleeve hole to sleeve and connect with athreadedly-connecting element; a bottom surface of the driving member 40of this embodiment has an insert column 45 protruding outside of thehead 31 from the through hole 34. In addition, a quick snap mechanism46, as shown in FIGS. 5, 8 and 9, is provided in the driving member 40,and includes a rod 47 slidably installed in a slideway 401 of thedriving member 40. When the rod 47 is pressed, a bead 48 can be pushedto expose the bead 48 from the insert column 45 to snap with a socket. Aspring 49 can be used to reposition the rod 47. The quick snap mechanism46 is a conventional component and is not a main subject matter of theinvention, so it will not be further described.

A quantity of the rollers 50 is the same as a quantity of the sides 41of the driving member 40, that is, the wrench 20 in the preferredembodiment of the specification has six rollers 50.

The reversing knob 60 is generally disk-shaped, and the rollers 50 arearranged in a circle and pivotally disposed on a bottom surface of thereversing knob 60 at equal intervals. Please refer to FIG. 8, a top endof each of the rollers 50 is pivotally connected to the bottom surfaceof the reversing knob 60 by a pivot shaft 52 so that the rollers 50 arecapable of rotating freely. In this embodiment, each of the pivot shafts52 is an independent member, and its two ends are respectively pivotallydisposed in a pivot hole 61 in the bottom surface of the reversing knob60 and in a pivot hole 51 in a top surface of each of the rollers 50.Please refer to FIG. 12 for a cross-sectional view of a second preferredembodiment of the roller wrench 20 of the invention (the same componentsuse the reference numbers of the first preferred embodiment). Each ofthe pivot shafts 52 can also be integrally formed with each of therollers 50, and its free end is pivotally disposed in the pivot hole 61of the reversing knob 60. In a similar way, in implementation, each ofthe pivot shafts 52 can also be integrally formed with the reversingknob 60, and its free end is pivotally disposed in the pivot hole 51 ofeach of the rollers 50.

Please refer to FIGS. 8 and 9, the rollers 50 and the reversing knob 60are installed in the head 31, the rollers 50 are placed in the circularchamber 32, and each of the rollers 50 is located between one of thesides 41 of the driving member 40 and a peripheral wall 33 of thechamber 32; the reversing knob 60 covers the top surface of the head 31,seals the chamber 32, and is capable of being rotated. A protruded wall43 provided on a top surface of the driving member 40 penetrates from athrough hole 62 in a center of the reversing knob 60. The chamber 32,the driving member 40 and the reversing knob 60 are concentric.

The elastic positioning component 70 is installed on a peripheralsurface of the driving member 40. This preferred embodiment provides thetwo elastic positioning components 70, which can be respectivelyinstalled on any two of the sides 41 of the driving member 40, forexample, on the two different sides 41 not adjacent to each other. Thetwo elastic positioning components 70 are arranged on the two sides 41of the driving member 40 at equal intervals (180 degrees apart) in thisembodiment. Each of the elastic positioning components 70 has an elasticelement 72 and an abutting member 74, which are installed in aninstallation hole 402 of one of the sides 41 of the driving member 40,and are capable of displacing in the installation hole 402. The abuttingmember 74 is preferably a bead, which is abutted by the elastic element72 to be exposed from the peripheral surface of the driving member 40.Each of the elastic positioning components 70 is located between the twolatching surfaces 44 of the side 41 where the elastic positioningcomponent 70 is located at, that is, located at the central area 42 ofthe side 41. As shown in FIG. 9, the abutting member 74 of each of theelastic positioning components 70 restricts displacement of one of therollers 50. Since all the rollers 50 are pivotally connected to thereversing knob 60, the rollers 50 have a relationship of movingsimultaneously and are incapable of moving independently. As shown inthe figures, when some of the rollers 50 are restrained by the elasticpositioning components 70 and incapable of moving freely, all therollers 50 are incapable of moving freely. Therefore, the two elasticpositioning components 70 simultaneously restrain all the rollers 50 toposition the rollers 50 and the reversing knob 60.

The usage state of the roller wrench 20 will be described hereinafter.The reversing knob 60 is capable of moving the rollers 50 to a firstposition or a second position to switch the roller wrench 20 indifferent operating directions. Based on the directions of FIGS. 4, 9and 10, when the reversing knob 60 is turned counterclockwise, thereversing knob 60 can be switched to the first position, and the rollers50 can be moved to the first positions as shown in FIG. 9, so that eachof the rollers 50 contacts with a latching surface 44 a at a left edgeof the corresponding side 41; when the reversing knob 60 is turnedclockwise, the reversing knob 60 is switched to the second position, andthe rollers 50 are moved to the second positions as shown in FIG. 10, sothat each of the rollers 50 contacts with a latching surface 44 b at aright edge of the corresponding side 41. In order to facilitateidentification of the first position and the second position, in thisspecification, the reference numeral 44 a represents the latchingsurface at the left edge, and the reference numeral 44 b represents thelatching surface at the right edge. When collectively referring to thelatching surface, it is indicated by the reference numeral 44.

FIG. 9 shows that the reversing knob 60 switches the rollers 50 to thefirst positions, at this time, each of the rollers 50 contacts with thelatching surface 44 a at the left edge of the corresponding side 41; thetwo elastic positioning components 70 are capable of restricting therollers 50 at the first positions, so that the rollers 50 are incapableof moving to the second positions, at the same time, the reversing knob60 also remains positioned at the first position.

On the outer side 442 of each of the latching surfaces 44 a, a gapbetween each of the latching surfaces 44 a and the peripheral wall 33 ofthe chamber 32 gradually decreases, and on the inner side 441 of each ofthe latching surfaces 44 a, a gap between each of the latching surfaces44 a and the peripheral wall 33 gradually increases. When the rollers 50are at the first positions, and the wrench 20 is turned clockwise, therollers 50 move toward a direction (that is, toward the outer sides 442of the latching surfaces 44 a) of a small gap between the latchingsurfaces 44 a and the peripheral wall. Therefore, each of the rollers50, each of the latching surfaces 44 a and the peripheral wall 33 of thechamber 32 are latched with one another, and the wrench 20 is capable ofdriving the driving member 40 to rotate clockwise, thereby rotating athreadedly-connecting element clockwise. Conversely, when the wrench 20is turned counterclockwise, the rollers 50 will move toward a directionof a large gap, each of the rollers 50, each of the latching surfaces 44a and the peripheral wall 33 of the chamber 32 are incapable of latchingwith one another, and the wrench 20 is incapable of driving the drivingmember 40 to rotate. With this disengaging-engaging effect, the wrench20 is capable of rotating a threadedly-connecting elementunidirectionally (clockwise).

Please refer to FIG. 9, since the outer side 442 of each of the latchingsurfaces 44 a(44) is an inward concave design, an included angle βbetween each of the latching surfaces 44 a and the peripheral wall 33 ofthe chamber 32 is smaller, and a width of a gap between each of thelatching surfaces 44 a and the peripheral wall 33 changes relativelygradually, that is, a gap between each of the latching surfaces 44 a andthe chamber 32 does not reduce quickly, so when each of the rollers 50moves toward a direction of a small gap, each of the rollers 50 iscapable of moving a longer distance. Using a center c of each of thesides 41 as a starting point, a distance d of the roller 50 movingtoward a position where the gap is small is longer, so that each of therollers 50, each of the latching surfaces 44 a and the peripheral wall33 are capable of effectively latching with one another and producingdisengaging-engaging function without the occurrence of slippage andlosing effect.

When the reversing knob 60 is rotated clockwise to the second position,the rollers 50 are moved to the second positions and respectivelycontact with the latching surfaces 44 b at the right edges of the sides41, as shown in FIG. 10. In the process of the rollers 50 moving fromthe latching surfaces 44 a at the left edges to the latching surfaces 44b at the right edges, the two elastic positioning components 70 will becompressed, as shown by an imaginary line, so that the abutting members74 will be moved into the driving member 40, after the rollers 50 havepassed over the abutting members 74 and moved to the latching surfaces44 b at the right edges, the abutting members 74 of the two elasticpositioning components 70 will be elastically pushed out by the elasticelements 72, and the abutting members 74 will position the rollers 50 onthe latching surfaces 44 b at the right edges, and also position thereversing knob 60 at the second position.

When the rollers 50 are positioned at the second positions as shown inFIG. 10, and the wrench 20 is rotated counterclockwise, each of therollers 50 will move toward a direction (that is, toward the outer sides442 of the latching surfaces 44 b) of a small gap between each of thelatching surfaces 44 b and the peripheral wall 33. Therefore, each ofthe rollers 50, each of the latching surfaces 44 b and the peripheralwall 33 of the chamber 32 are latched with one another, and the wrench20 is capable of driving the driving member 40 to rotatecounterclockwise. Conversely, when the wrench 20 is turned clockwise,the rollers 50 will move toward a direction of a large gap, each of therollers 50, each of the latching surfaces 44 b and the peripheral wall33 of the chamber 32 are incapable of latching with one another, and thewrench 20 is incapable of driving the driving member 40 to rotate.Thereby, the wrench 20 is capable of rotating a threadedly-connectingelement unidirectionally (counterclockwise).

The wrench 20 of this embodiment (and the wrench 20 of the secondpreferred embodiment of FIG. 12) has the following efficacies of beingcapable of overcoming the disadvantages of the conventional structure.In the structural design of the invention, the elastic positioningcomponent 70 has the functions of the wall 171 and the elasticpositioning component 18 of the conventional structure of FIG. 1, thatis, the elastic positioning component 70 is capable of reliablypositioning the rollers 50 at the first positions or the secondpositions, unless an operator turns the reversing knob 60 by hand, therollers 50 remain in position and are incapable of moving from the firstpositions to the second positions or from the second positions to thefirst positions. At the same time, the elastic positioning component 70positions the reversing knob 60 at the first or second position.

Secondly, as for positioning the reversing knob 60 and the roller 50,the invention only needs to install the elastic positioning component 70in the driving member 40, the reversing knob 60 and the roller 50 can bepositioned by using the elastic abutting relationship between theelastic positioning component 70 and the corresponding roller 50.Compared with the elastic positioning component 18 and the positioningholes 153, 154 of the conventional structure, the elastic positioningstructure of the invention is significantly more simplified. Therefore,the structure of the invention is easier to be manufactured and canreduce costs.

Furthermore, since the outer side 442 of each of the latching surfaces44 of the invention is an inward concave design, when each of therollers 50 moves toward a direction of a small gap, each of the rollers50 is capable of moving a longer distance (as shown in FIG. 9), so thateach of the rollers 50, each of the latching surfaces 44 and theperipheral wall 33 of the chamber 32 are capable of effectively latchingwith one another and producing disengaging-engaging function. Inaddition, please refer to FIG. 11, since a degree of the included angleβ between the latching surface 44 and the peripheral wall 33 is small,when latching is formed, a contact point G between the peripheral wall33 and the roller 50, and a contact point H between the latching surface44 and the roller 50 can be closer to a center of the roller 50, whichare capable of increasing a torque that the wrench 20 is capable ofwithstanding.

FIGS. 13 to 15 are a third preferred embodiment of a roller wrench 140of the invention, which also comprises: a body 150, a driving member160, a plurality of rollers 170, a reversing knob 180 and at least oneelastic positioning component 190.

A head 151 of the body 150 is recessed with a circular chamber 152.

The driving member 160 is installed in the circular chamber 152 of thehead 151, and is a regular polygonal component, such as a regularhexagon, and has six sides 161, each of the sides 161 has a central area162 and two inwardly recessed latching surfaces 164 located on two sidesof the central area 162. Each of the latching surfaces 164 has an innerside 1641 connected to the central area 162 and an outer side 1642 awayfrom the central area 162, and a concave state of each of the latchingsurfaces 164 is gradually recessed inwardly from the inner side 1641 tothe outer side 1642. A protrusion 1611 is formed between the outer sides1642 of the two adjacent latching surfaces 164 of the two adjacent sides161. The included angle α is formed between each of the latchingsurfaces 164 and each of the central areas 162, and a degree of theincluded angle α is between 1 degree and 10.4 degrees, or between 2.2degrees and 10.4 degrees, preferably between 4.3 degrees and 8.8degrees. An included angle β is also formed between each of the latchingsurfaces 164 and a peripheral wall 153 of the chamber 152.

The six rollers 170 are installed in the circular chamber 152 and arerespectively located between the six sides 161 and the peripheral wall153 of the chamber 152.

A bottom surface of the reversing knob 180 is provided with six walls182, which are arranged in a circular shape at equal intervals, and hassix limiting grooves 184 formed between the six walls 182. The reversingknob 180 is installed on a top surface of the head 151, the walls 182and the limiting grooves 184 are located in the chamber 152; and the sixrollers 170 are respectively limited in the six limiting grooves 184.

This embodiment has two elastic positioning components 190 installed ona peripheral surface of the driving member 160. The two elasticpositioning components 190 can be installed on any two of the sides 161of the driving member 160, and each of the elastic positioningcomponents 190 is preferably disposed at a center of the side 161 wherethe elastic positioning component 190 is located at (for example,disposed in the central area 162 of the side 161), that is, locatedbetween the two latching surfaces 164 of the side 161. Each of theelastic positioning components 190 has an elastic element 192 and anabutting member 194, which are installed in an installation hole 1602 ofone of the sides 161 of the driving member 160, and the abutting member194 is abutted by the elastic element 192 to be exposed from theperipheral surface of the driving member 160.

The reversing knob 180 is capable of being switched between a firstposition and a second position, and driving the rollers 170 to displace.FIG. 14 shows that the reversing knob 180 is located at the firstposition, and at the same time, the limiting grooves 184 of thereversing knob 180 position the rollers 170 at the first positions, sothat the rollers 170 contact with the latching surfaces 164 at leftedges of the sides 161. The abutting members 194 of the two elasticpositioning components 190 are capable of limiting the rollers 170 atthe first positions, thereby positioning the reversing knob 180 at thefirst position.

When the reversing knob 180 is rotated to the second position, as shownin FIG. 15, the reversing knob 180 drives the rollers 170 to move to thesecond positions and contact with the latching surfaces 164 at rightedges of the sides 161. After switching, the abutting members 194 of thetwo elastic positioning components 190 limit the rollers 170 at thesecond positions, thereby positioning the reversing knob 180 at thesecond position.

The latching surfaces 164 of the driving member 160 of this embodimentare capable of causing the driving member 160, the rollers 170, and theperipheral wall 153 of the chamber 152 to be effectively latched withone another and to produce effective disengaging-engaging function, anda contact point between the peripheral wall 153 of the chamber 152 andthe roller 170 and a contact point between the latching surfaces 164 andthe roller 170 to be closer to a center of the roller 170.

The two elastic positioning components 190 are capable of effectivelypositioning the reversing knob 180 and the rollers 170 at the firstpositions or the second positions. Compared with the conventionalstructure in FIG. 1, the structure of the elastic positioning components190 of this embodiment is simpler, easy to be manufactured and canreduce costs.

It is to be understood that the above description is only preferredembodiments of the present invention and is not used to limit thepresent invention, and changes in accordance with the concepts of thepresent invention may be made without departing from the spirit of thepresent invention, for example, the equivalent effects produced byvarious transformations, variations, modifications and applications madeto the configurations or arrangements shall still fall within the scopecovered by the appended claims of the present invention.

What is claimed is:
 1. A roller wrench comprising: a body with a head, acircular chamber being disposed in the head; a driving member being aregular polygonal component with a plurality of sides, the drivingmember being installed in the chamber of the head and capable ofrotating in the chamber; a plurality of rollers with a quantity the sameas a quantity of the sides of the driving member, the rollers beinginstalled in the chamber and respectively located between the sides ofthe driving member and a peripheral wall of the chamber; and a reversingknob rotatably installed on the head, the reversing knob being capableof driving the rollers to move in the chamber, so that each of therollers moving between one edge and another edge of each of the sides ofthe driving member; further comprising: at least one elastic positioningcomponent, each of the elastic positioning components being installed onone of the sides of the driving member and located between the two edgesof the side, and capable of elastically moving into the driving memberor protruding from a peripheral surface of the driving member; theelastic positioning component being moved into the driving member whenbeing compressed; and being protruded from the driving member when notbeing acted on by an external force; at least one of the rollers beinglimited by the at least one elastic positioning component to positionthe rollers and the reversing knob; when the reversing knob beingrotated, the roller pressing the elastic positioning component to makethe rollers moving from one of the edges to the other edge of each ofthe sides of the driving member respectively.
 2. The roller wrench asclaimed in claim 1, wherein each of the elastic positioning componentsis located at a center of the corresponding side that the elasticpositioning component is installed on.
 3. The roller wrench as claimedin claim 1, wherein at least one installation hole is recessed on atleast one of the sides of the driving member; the at least one elasticpositioning component is installed in the installation hole and can bemoved into or protruded from the installation hole.
 4. The roller wrenchas claimed in claim 3, wherein the elastic positioning component has anelastic element and an abutting member installed in the installationhole and capable of displacing in the installation hole, the abuttingmember is abutted by the elastic element and protruded from theperipheral surface of the driving member; and the abutting member of theelastic positioning component limits one of the rollers.
 5. The rollerwrench as claimed in claim 1, wherein the rollers are arranged in acircle at equal intervals, and one end of each of the rollers isrotatably pivotally connected to one end surface of the reversing knob;when the reversing knob is rotated, the reversing knob drives therollers to displace.
 6. The roller wrench as claimed in claim 1,comprising at least two elastic positioning components respectivelyinstalled on at least two sides of the driving member.
 7. The rollerwrench as claimed in claim 1, comprising two elastic positioningcomponents respectively disposed on the two sides of the driving memberand 180 degrees apart.
 8. The roller wrench as claimed in claim 1,wherein each of the sides of the driving member has a central area, aconcave latching surface is respectively provided on two sides of thecentral area, each of the latching surfaces has an inner side connectedto the central area and an outer side away from the central area, aconcave state of each of the latching surfaces is gradually concavedinwardly from the inner side to the outer side; an included angle with asmall degree is formed between each of the latching surfaces and thecentral area of each of the sides; when each of the rollers is locatedon one edge of each of the sides, a peripheral surface of the rollercontacts with the corresponding latching surface and the peripheral wallof the chamber, so that the body, the rollers and the driving member arelatched with one another.
 9. The roller wrench as claimed in claim 8,wherein each of the elastic positioning components is installed on thecentral area of one of the sides of the driving member.
 10. The rollerwrench as claimed in claim 1, wherein one end surface of the reversingknob is provided with a plurality of walls arranged in a circle at equalintervals; a plurality of limiting grooves are respectively formedbetween the walls, the walls and the limiting grooves are located in thechamber; and the rollers are respectively disposed in the limitinggrooves.